Endocrine Abstracts

Introduction: We present the outcome for the first 21 patients undergoing neuronavigation–guided, endoscopic transphenoidal surgery for pituitary dependent Cushing’s disease in our centre since August 2001. All operations were consecutive, and undertaken by the same neurosurgeon and endoscopic nasal surgeon.

Methods: Records are available for 20 cases. Pre and post operative management of cases was led by the endocrine team with standard assessments, including pituitary MRI, limited bone window CT and bilateral inferior petrosal sinus sampling. Cure was defined as a cortisol level at 9 am below 50 nmol/l on two separate occasions in the immediate post operative period. A ‘significant reduction’ in cortisol burden was defined as two separate cortisol measurements <100 nmol/l at 9 am post operatively. Patients have been followed for a median of 42 months (range 1–73).

Results: Preoperative pituitary MRI identified a macroadenoma in 6 patients (30%); a microadenoma was identified in 8 cases (40%) and no radiological abnormality was evident in 5 (25%). In one patient no MRI details are available. Two patients (10%) had undergone previous transphenoidal surgery. Of the 6 patients with macroadenomas surgical cure was not achieved. Control in these individuals has been achieved with pituitary radiotherapy and medical treatment. Of the remaining 14 patients, surgical cure was achieved in 7 with a significant reduction in cortisol burden in 3. Thus, significant improvements in disease was achieved in 71% of patients with microadenomas. In total, 11 patients (55%) received postoperative radiotherapy.

Complications: A learning curve has previously been demonstrated within this cohort of patients. 5 patients developed post operative CSF leak. Two have developed persistent diabetes insipidus.

Conclusions: This technique minimises nasal damage and provides improved visualisation for the surgeon. In skilled hands this is an alternative to conventional transphenoidal microscopic surgery in managing cases of pituitary dependent Cushing’s disease.